RFR: 8013395 StringBuffer.toString performance regression impacting embedded benchmarks

Martin Buchholz martinrb at google.com
Fri May 10 18:34:07 UTC 2013


On Fri, May 10, 2013 at 10:36 AM, Mike Duigou <mike.duigou at oracle.com>wrote:

> The implementation looks OK to me. I like Peter's suggestion of caching
> the char[] rather than string.
>
> I do wish that the cache could be in a soft reference but understand that
> there are tradeoffs to doing so. I am worried about leaks with this
> implementation.
>
> Another possibility, to go totally nuts, is to consider implementing a
> form of copy-on-write-following-toString. This would be the exact opposite
> of "minimal set of changes to address this specific problem" and probably
> not wise to attempt for Java 8.
>
> Just as an FYI, this issue has in-flight conflicts with Martin's ongoing
> CharSequence.getChars patch.
>

I agree with Alan about the cringe factor, and I prefer the old
implementation.  But it's understandable and not too terrible for real
world users, because no one outside of unrealistic benchmarks should be
making heavy use of StringBuffer.

And: Yes, I will need to update my own changes to StringB*.



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